I recently changed my cable modem and afterwards my Orbi RBR50 network is not behaving as expected. Most devices got back onto the network with no problem, but some, notably my Synology NAS, have not been able to do that. They previously worked with no problem. My NAS is able to get onto the local network but it cannot get a signal for the internet. This is really confusing to me. Should I reset the whole network and try to set everything up again, satellites and all? Or is there something I can do in the Orbi admin settings to troubleshoot specific devices? Thank you.

(Sorry for the delay. Oscar Program on TV. Have actually seen several of the movies....) This appears to be a situation where the UPnP reservation has 'stuck' in the Orbi while the NAS changed IP address. Normally, (is anything about computers 'normal'?), an Orbi router creates an IP subnet on the LAN side that starts with 192.168.1 with the devices starting at 192.168.1.1 (the router) and the rest of the devices going up until they reach 192.168.1.254. When the router itself is assigned an IP address of 192.168.1.(something), the Orbi says, "oh, s**t" and creates the LAN subnet at 10.0.0.x, with the router being 10.0.0.1. See the Wikipedia article on private IP Networks: https://en.wikipedia.org/wiki/Private_network With all those IP subnets to choose from, Netgear somehow decided to pick that one. The key to this is that for devices to function correctly on the LAN, they must be in the correct IP subnet. If the change in the ISP modem has resulted in the Orbi deciding to change the LAN subnet from 10.0.0.x to 192.168.1.x, then any device which has an IP address of 10.0.0.x is essentially "lost". What this look like is that when the NAS had an IP address in the 10.0.0.x subnet, it used UPnP to forward ports to itself. Now that it has an IP address in the 192.168.1.x subnet, those ports are forwarded to something that no longer exists. Honestly, I am not entirely sure how to fix this. My first thought is: Go into the UPnP page and delete all those port forwarding entries going to 10.0.0.x (whatever) Access the NAS management page (web, correct?) and tell it to set UPnP again. This would have driven me to drink. (Oh, wait. I am drinking.)

Could you please make a screen shot of the top part of the LAN Setup screen? i.e. My goal is to drive a stake through this issue of "which IP subnet is everything in?"

One key piece of information is specifics about the two cable modems: What brand/model was the previous cable modem? What brand/model is the current cable modem? For example, if the previous cable modem was "just a modem" (no WiFi, no router functions), the the NAS could easily have opened ports to allow access from the internet. Most NAS systems include UPnP features to make port forwarding automatic. If the current cable modem includes router functions, then it will block connections from the internet and what the NAS does with the Orbi router will not be successful. If this is the case, resetting everything will not be productive.

Ohh actually it’s the same modem, from the cable company, but previously it had its internal wi-fi router turned ON, and when I had it reset I asked the cable company to turn the router OFF entirely. I thought that the modem had been doing NAT alongside the Orbi router, so I thought it would be best to disable that. So in theory this should be easier for the NAS to connect to the internet, no?

Maybe it would be a good idea to double check that the cable tech did what was asked. i.e. Compare the IP address that the Orbi router reports on its WAN interface against the public IP address from one of those "What's my IP?" web sites: On the Orbi web interface http://orbilogiin.net ) the Advanced Tab home screen will show the IP address assigned to the Orbi WAN port: Open a web browser to (https://whatismyipaddress.com ) The IPv4 address should match the Internet Port address exactly.

Some devices not connecting to Orbi RBR50 after new cable modem install

17 Replies

CrimpOn
Guru - Experienced User
Mar 12, 2023
One key piece of information is specifics about the two cable modems:

What brand/model was the previous cable modem?

What brand/model is the current cable modem?

For example, if the previous cable modem was "just a modem" (no WiFi, no router functions), the the NAS could easily have opened ports to allow access from the internet. Most NAS systems include UPnP features to make port forwarding automatic.

If the current cable modem includes router functions, then it will block connections from the internet and what the NAS does with the Orbi router will not be successful.

If this is the case, resetting everything will not be productive.
- mrsubtraction
  Guide
  Mar 13, 2023
  Ohh actually it’s the same modem, from the cable company, but previously it had its internal wi-fi router turned ON, and when I had it reset I asked the cable company to turn the router OFF entirely. I thought that the modem had been doing NAT alongside the Orbi router, so I thought it would be best to disable that.
  
  So in theory this should be easier for the NAS to connect to the internet, no?
  - CrimpOn
    Guru - Experienced User
    Mar 13, 2023
    Maybe it would be a good idea to double check that the cable tech did what was asked.
    
    i.e. Compare the IP address that the Orbi router reports on its WAN interface against the public IP address from one of those "What's my IP?" web sites:
    
    On the Orbi web interface http://orbilogiin.net ) the Advanced Tab home screen will show the IP address assigned to the Orbi WAN port:
    
    Open a web browser to (https://whatismyipaddress.com ) The IPv4 address should match the Internet Port address exactly.

Forum Discussion

Some devices not connecting to Orbi RBR50 after new cable modem install